Calculating the Present Value of an Annuity with Annual Compounding

  • Thread starter Thread starter TonyC
  • Start date Start date
  • Tags Tags
    annuity
AI Thread Summary
To calculate the present value of an annuity with annual compounding, the formula used is A = P[(1 + r)^m - 1]/r, where P is the annual deposit, r is the interest rate, and m is the total number of deposits. In this case, P is $1000, r is 0.045, and m is 18. A common mistake noted is a potential typo in the formula, which should be correctly formatted as A = 1000[(1 + 0.045)^{18} - 1]/0.045. Additionally, it's pointed out that the problem may actually be a simple compound interest calculation rather than an annuity problem. Properly applying the correct formula is essential for accurate results.
TonyC
Messages
86
Reaction score
0
I am having trouble with the following problem:
What will be the value of an annuity in today's dollars if $1000 is to be deposited for 18 years into an account paying 4.5% interest compounded annually?

I used the following formula (I'm guessing I've figured something incorrectly)

A= P[(1 + r)^m - 1]/r

P=1000
r=i/n
i=4.5% or .045
n=1
t=18
m=n(t) or 18

1000[1 + .045)^18 - 1/.045

I know this is incorrect because my choices are multiple choice
 
Physics news on Phys.org
There are a couple of possibilities. One, your last equation either has a typo or you did it wrong:

1000[1 + .045)^18 - 1/.045 ==> should be \frac{1000[(1 + .045)^{18} - 1]}{.045}

The second is that it's not an annuity problem but rather a simple compound interest problem FV = PV(1+r)^m
 
Thank you very much.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Trying to understand the logic behind adding vectors with an angle between them'
My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
Back
Top